Frost Layer Research Articles

Superhydrophobic and photothermal SiC/TiN durable composite coatings for passive anti-icing/active de-icing and de-frosting

Facing the problems of fossil energy shortage and solid surface icing, the use of solar energy to remove surface ice accumulation is a promising solution. Here, we propose a superhydrophobic coating with a photothermal effect for anti-icing and de-icing and defrosting performance. We designed the coating using a simple secondary spray method. That is, a bonding substrate (epoxy resin) is first constructed on the glass substrate, then a protective layer (polydimethylsiloxane(PDMS)) mixed with SiC/TiN composite particles is sprayed onto the epoxy resin surface, and finally dried to obtain a photothermal superhydrophobic coating. In this design, the coating shows (I) excellent superhydrophobicity (water contact angle = 155°, sliding angle = 4°), (II) excellent photothermal effect (the surface temperature of obtain coating rapidly rose to 111.8 °C under 1 sun), and (III) good chemical and mechanical stability. As a result, the coating shows excellent anti-icing, de-icing, and defrosting properties. For example, the coating can significantly extend the icing time. In the face of surface frozen water droplets, frost layers, and large areas of ice cover, the coating can rapidly photothermally remove surface ice layers under 40 mW cm−2 light irradiation. As a result, the coating is simple to prepare and has excellent superhydrophobic, photothermal anti-icing/de-icing, and defrosting properties. The study is of great significance for multifunctional applications.

A frost model based on the frost layer's supporting function

The existence of frost has adverse effects the normal operation of air source heat pumps. Therefore, establishing an accurate frost model is of great significance to suppressing the formation of frost layers on cold surfaces. Since the frost layer grows gradually and cumulatively layer by layer in the actual physical frosting process, it is important to consider the supporting function of the lower frost layer in the process. This study proposes the use of the ice volume fraction threshold of the frost layer to determine whether the supporting condition is satisfied, in addition to using the threshold to determine the occurrence of frosting. A new frost model is developed with the given volume fraction threshold fitting formula. In order to verify the accuracy of the proposed model, the simulation results were compared with 17 groups of experimental results from four representative experiments. It was found that the simulation results of this model were in good agreement with the experimental data, and the average error of thickness did not exceed 4.9%, while the average error of density was less than 5.5%.

Freezing propagation of condensate droplets at early stage of frosting on vertical hydrophobic surface

As condensate droplets formed at the early stage of frosting are the foundation of frost layer growth, to study the freezing propagation of condensate droplets is of great significance to understand the frosting process. In this paper, the influencing factors of lateral spreading of frost crystals and freezing propagation modes of condensation droplets were discussed by visualization experiments, and the propagation mechanism was revealed combined with theoretical analysis. It is observed that condensate droplets relies on the lateral spreading of frost crystals to realize the freezing propagation and frost crystals diffuse to the center of the cold surface with the help of freezing droplets. The lateral spreading of frost crystals is the key to achieve freezing propagation of condensate droplets, which is accompanied by the evaporation of droplets with small size. The freezing propagation of condensate droplets is affected by the lateral spreading rate of frost crystals and the droplet spacing. Increasing the contact angle of the cold surface reduces the freezing propagation rate and delay frost formation. Interestingly, two freezing propagation modes, “contact-freeze” and “absorption-freeze”, are observed when the frost crystals contact the subcooled droplets. Increasing the surface contact angle or reducing the contact angle hysteresis can increase the frequency of the “absorption-freeze” mode, which helps to reduce the freezing propagation rate of condensate droplets.

Towards the pseudo-2D modeling of frost growth between cold parallel plates

When a heat recovery ventilator is operating under winter conditions, the water vapor present in the exhaust airflow can lead to frost formation that depends on the outside air temperature, the heat exchanger plate temperature and their spacing, the exhaust air flow and its humidity. In this study, an available 1D frost formation model, based on frost growth and its densification, is improved and validated using experimental data available in the literature and measurements performed on a new test bench before extending the model on a 2D geometry. The objective of this study is to evaluate accurately the frost growth between cold parallel plates. The frost densification depends on the square root of time and the ratio of supercooling and supersaturation degrees. An energy balance equation for the heat conduction through the frost layer is solved and the heat and mass transfer from the moist air to the frost layer is used as a convergence criterion to predict the frost surface temperature. The proposed pseudo-2D model shows that the airflow from a 2.5 mm parallel plate spacing heat exchanger is reduced by 33% over a 25 min period due to frost growth. Using a 4.0 mm spacing, the airflow reduction gets only 5% over the same time period. It shows that larger plate spacing airflow are less affected by frost growth. After 25 min, the 2.5 mm spacing heat recovery efficiency decreases from 87% to 77% while for the 4.0 mm spacing, it decreases from 60% to 55%.

Characterization of the KATRIN cryogenic pumping section

The KArlsruhe TRItium Neutrino (KATRIN) experiment aims to determine the effective anti-electron neutrino mass with a sensitivity of 0.2eV/c2 by using the kinematics of tritium β-decay. It is crucial to have a high signal rate which is achieved by a windowless gaseous tritium source producing 1011β-electrons per second. These are guided adiabatically to the spectrometer section where their energy is analyzed. In order to maintain a low background rate below 0.01cps, one essential criteria is to permanently reduce the flow of neutral tritium molecules between the source and the spectrometer section by at least 14 orders of magnitude. A differential pumping section downstream from the source reduces the tritium flow by seven orders of magnitude, while at least another factor of 107 is achieved by the cryogenic pumping section where tritium molecules are adsorbed on an approximately 3K cold argon frost layer. In this paper, the results of the cryogenic pumping section commissioning measurements using deuterium are discussed. The cryogenic pumping section surpasses the requirement for the flow reduction of 107 by more than one order of magnitude. These results verify the predictions of previously published simulations.

Frosting characteristics of superhydrophobic surface under desublimation frosting conditions

Frosting type of an air source heat pump under frosting conditions is divided into condensation frosting and desublimation frosting. Superhydrophobic surface has been proved to have good anti-frosting performance for air source heat pump under condensation frosting conditions. However, its frosting characteristics and anti-frosting performance are not clear under desublimation conditions. Therefore, a visual frosting experiment system was built to achieve frosting characteristics of superhydrophobic surface under desublimation conditions. The experimental results show that the frosting process of the superhydrophobic surface is similar to condensation frosting even under the desublimation conditions. The water vapor still forms condensate droplets and the frost crystals grow on the surface of the freezing droplets, while the frosting of the bare surface is very different from condensation frosting and the water vapor directly become solid frost crystals. The frost thickness of the bare surface is 1.27, 2.70 and 2.05 times than that of the superhydrophobic surface under various desublimation conditions, which indicates that the superhydrophobic surface can also inhibit frost layer growth under desublimation conditions. The reason for the preferential formation of condensation frosting on superhydrophobic surface under desublimation conditions was analyzed. The nucleation critical radius, nucleation barrier and nucleus surviving rate generate by desublimation and the supersaturation requires for desublimation on the cold surface with big contact angle are much larger than that of condensation. These are the main reasons why the superhydrophobic surface still preferentially chooses condensation frosting under desublimation conditions.

Design of drain hole for household refrigerator fan module based on experiments and CFD simulation

In refrigerator, the frost accumulated at the evaporator surface and melt with the defrost heater over the operation cycles. While the undesirable airflow from a drain hole in the refrigerator fan (R-fan) module can deteriorate the frost layer formation and defrost process. The thermal resistance increased by the frost layer can significantly affect the cooling capacity and power consumption of refrigerators. Different from the research on frost generation mechanisms, this study focused on product performance related to frost accumulation and flow features. The relationship between frost accumulation and airflow from drain hole was investigated by combining the experimental method and computational fluid dynamics (CFD) analysis without phase change. A new drain hole design with a circular shape was selected considering Laplace pressure for stable drainage. In CFD results, proposed model shows significant reduction of disorderly airflow around the evaporator and improvement of the performance including the flow rate delivered to the refrigerator and temperature distribution around the evaporator. The validation test of the proposed model fabricated by 3D printer was also conducted. The results corresponded well with the simulation result. The in-situ experimental results showed that the flow loss from the R-fan module drain hole and the average defrost cycle time were improved with a reduction of 28.7% and 8.0% compared with the original model, respectively. Although the internal structure of different products may be slightly different, the research results can be applied to products with similar defects for product development and improvement.

Localized Characteristics of the First Three Typical Condensation Frosting Stages in the Edge Region of a Horizontal Cold Plate.

Condensation frosting usually causes a negative influence on heat exchangers employed in engineering fields. As the relationships among the first three typical condensation frosting stages in the edge regions of cold plates are still unclear, an experimental study on the localized condensation frosting characteristics in the edge region of a cold plate was conducted. The edge effects on the water droplet condensation (WDC), water droplet frozen (WDF) and frost layer growth characteristics were quantitatively investigated. The results showed that the number of droplets coalescing in the edge-affected regions was around 50% greater than in the unaffected regions. At the end of the WDC stages, the area-average equivalent contact diameter and coverage area ratio of water droplets in the edge-affected regions were 2.69 times and 11.6% greater than those in the unaffected regions under natural convection, and the corresponding values were 2.24 times and 9.9% under forced convection. Compared with the unaffected regions, the WDF stage duration in the edge-affected regions decreased by 63.6% and 95.3% under natural and forced convection, respectively. Additionally, plate-type and feather-type frost crystals were, respectively, observed in natural and forced convection. The results of this study can help in the better understanding of the condensation frosting mechanism on a cold plate, which provides guidelines for optimizing the design of heat exchanger structures and system control strategies facing frosting problems.

Experimental study on anti-frosting performance of superhydrophobic surface under high humidity conditions

• Frosting experiment of superhydrophobic surface under high humidity was performed. • Self-jumping of condensate droplets always existed at early stage of frosting. • The freezing time of droplets was delayed compared with that of bare surface. • Ambient humidity had effects on frost crystal pattern and frost layer thickness. • Superhydrophobic surface had good anti-frosting performance under high humidity. The ambient humidity has a significant influence on the frosting characteristics of cold surface. In order to achieve the anti-frosting performance of superhydrophobic surface under high humidity conditions, visualization were performed to study the frosting characteristics of superhydrophobic surface at relative humidity of 65%, 75%, 85% and 95%. The absolute humidity was 6.11, 7.05, 7.99 and 8.93 g/m 3 , respectively. Experimental results showed that the phenomenon of merging and self-jumping of condensate droplets always existed at early stage of frosting, even under high humidity conditions. Although the freezing time of condensate droplets decreased with the increase of ambient humidity, it was delayed compared with bare surface. At the frost layer growth stage, the ambient humidity had effects on the frost crystal pattern and frost layer thickness of superhydrophobic surface. When the relative humidity was 65%, the surface was covered with sword-shaped frost crystals, while the frost layer was thicker and denser at 95%. The frost layer thickness of superhydrophobic surface was 0.78, 0.58, 0.64 and 0.74 times of that of bare surface, when the relative humidity was 65%, 75%, 85% and 95%, respectively. This indicated that the superhydrophobic surface still had good anti-frosting performance under high humidity conditions.

Intelligent computing approaches to forecast thickness and surface roughness of frost layer on horizontal plates under natural convection

There is no existing predictive model for frost layer thickness and surface roughness on horizontal cold plates under the natural convection conditions. Accordingly, intelligent approaches were designed based upon 782 data for frost thickness and 191 data for frost surface roughness, which covered four stages of frosting process. Three machine learning methods of multilayer perceptron (MLP), Gaussian process regression (GPR), and radial basis function (RBF) were employed to design the predictive models for frost characteristics over horizontal cold plates in the natural convection environment. For the frost thickness, although almost all models provided excellent outputs, the RBF based model showed the highest accuracy with average absolute relative error (AARE) and coefficient of determination (R2) values of 1.23% and 99.93%, respectively, for the tested data. The RBF based model presented the superior results for frost surface roughness with an AARE of 1.21% for all analyzed data. The proposed predictive methods were capable of predicting the impact of surface temperature on the frost characteristics at various stages of the process. A statistical analysis of earlier correlations revealed large deviations from the measured data caused by the differences in operating conditions. Thus, new explicit correlations were developed using the intelligent method of genetic programming, which showed the AAREs of 4.61% and 16.72% for frost thickness and frost surface roughness, respectively.

Preliminary study of CO2 frost formation during cryogenic carbon capture using tomography analysis

Cryogenic carbon capture (CCC) is a potential technological solution to reduce CO2 emissions and achieve the needed environmental targets. CCC provides a relatively compact solution to industries where more mature technologies would have difficulty scaling down economically. However, there is a lack of research on frost formation of CO2 within packed bed systems, despite the influence of the CO2 frost layer on thermal conductivity leading to excessive cooling costs. Understanding the rate of CO2 frost growth and accumulation within a packed bed is critical to the design of the capture column. Therefore, real-time quantitative imaging becomes increasingly desirable to study the CO2 frost formation during cryogenic carbon capture, but it may be difficult by most of the traditional measurement methods. This study aims to investigate the use of an Electrical Capacitance Tomography (ECT) to monitor the real-time CO2 frost formation in a fixed packed bed. In this work, the evolution of the permittivity distribution during the capture process has been investigated in detail by experiments, elucidating the effect of the bed material type and bed material temperature. An ECT sensor was constructed to measure frost distribution to elucidate the mechanisms of CO2 frost formation by first testing on ice frost in the packed bed. The ECT images of ice formation were reconstructed by measurement data with a conventional algorithm. The results show that ECT could effectively monitor the changes of relative permittivity caused by the frost formation in real-time. With the help of an image reconstruction algorithm, the outline and position of the permittivity change area can be monitored. These results indicate that ECT has the potential to be a novel technique for monitoring CO2 frost formation during cryogenic carbon capture.

Experimental study on the mechanism of ice layer formation in fractured rock masses in cold regions

The formation and growth of ice layers in fractured rock masses is one of the main causes of frost weathering in bedrock in cold regions. The mechanism of ice layer formation in fractured rock masses was simulated in this study by conducting frost weathering tests on a simulated rock mass with a vertical through fracture, which was fabricated by splicing two cement blocks. The test results were used to propose a novel mechanism for ice layer formation in terms of the initial crack-frost effect in which moisture mainly migrates in vapor form. The continuous accumulation and growth of these frosts eventually forms an ice layer that expands the crack, and the fractured rock simulation model undergoes frost-heaving damage. The frost layer on the rock wall in the negative temperature region is similar to the frosting process on the cold surface of thermodynamic studies. The relative humidity (RH) gradient and temperature gradient were shown to be the factors affecting water vapor migration, where the former plays a direct and dominant role, and the temperature gradient has a very limited direct effect on vapor migration.

Image-Analysis-Based Approach for Identification of Air Cooler Heat Transfer Degradation during Frosting Process

Fin-and-tube heat exchangers have been extensively used in many fields, especially in heat, ventilation, air-conditioning, and refrigeration systems. In the case of the operation of a fin-and-tube heat exchanger as an air cooler, frost formation is an important effect that should be taken into account. The frost accumulation process is undesirable since it deteriorates heat transfer due to the insulation of the frost layer as well as causing excessive pressure loss. The analysis of the effect of the frosting process on a fin-and-tube air cooler performance is presented in this paper. Based on long-term experimental investigations applied to the air cooler in a cold storage chamber, the general degradation of the heat exchanger performance is discussed. The influence of frost on the cooling capacity, by-pass factor, and thermal resistance is analysed. The temperature distribution of the air passing through the air cooler before and after the defrosting process is presented and discussed. A method for the assessment of the amount of frost formed at the air cooler surface, based on visualisation of the air cooler during operation and synchronised with the thermal measurements, is developed. The results show that the frosting process causes deterioration of the cooling capacity by up to 40% in the analysed case. Correlation is demonstrated between frost formation and heat transfer degradation in the air cooler.

Simulation of Forced Convection Frost Formation in Microtubule Bundles at Ultra-Low Temperature

Hypersonic vehicles are an important area of research in the aerospace field today. One of the important issues is the power of the engine. In order to achieve large-span flight speeds, a more efficient approach is to use combined power systems. However, the problem of pre-cooler icing can occur in combined engine applications. The flow in the pre-cooler is extremely complex. Outside the tube is the high-temperature wet air entering from the engine intake, and the tube cooling is the ultra-low temperature cooling medium. Icing not only increases the heat exchange resistance of the pre-cooler during operation and affects the heat exchange performance of the pre-cooler, but also causes a large total pressure loss, resulting in a degradation of the engine performance. There is a lack of research on the icing law of the pre-cooler under different parameters. Therefore, it is necessary to conduct a corresponding numerical calculation study on pre-cooler icing and explore the influence of various influencing factors on icing. In this paper, a mathematical model of icing (frost) is established for the frosting phenomenon that may occur during the operation of the pre-cooler. Additionally, the principle of heat and mass transfer in the icing process is described by the mathematical model, and the influence of different parameters on the frosting parameters is explored by using the computational fluid dynamics (CFD) method. The law of tube bundle icing under different parameters was calculated, and the variation laws of frost layer morphology and wet air pressure drop were obtained. The laws of tube bundle icing under different parameters were calculated, and the changes in frost layer pattern and wet air pressure drop when each parameter was changed, which can provide guidance for the design and application of pre-coolers in the future.

An experimental study on the dynamic frosting characteristics on the edge zone of a horizontal copper plate under forced convection

To retard the negative effects of frosting, it is necessary to better understand the frosting mechanism on cold surfaces. In this study, a systematical study on the dynamic frosting characteristics on the edge zone of a horizontal copper plate under forced convection was conducted. The results showed that the air velocity effect and edge effect on droplet condensation, frozen and frost layer growth characteristics were significant. The duration of droplet condensation stage decreased from 365 to 113 s with a decrease of 69.0% when air velocity increased from 0.5 to 2.5 m/s. Besides, the average freezing wave propagation velocity for Region I (an area where a row of water droplets closest to plate edge) was significantly larger than that for Region II (the remained area). As a result, the duration of droplet frozen stage for Region I was much shorter than that for Region II. Accordingly, frost layer amount for Region I was notably larger than that for Region II. Besides, the frost surface roughness for Region I increased as air velocity increased at the early frosting stage, but decreased as air velocity increased at the later frosting stage. The general turning point for frost surface roughness at 1.5 m/s surpassed the value at 0.5 m/s was around 21.4 × 10−6 m at 390 s, and that between 2.5 m/s and 1.5 m/s was around 30.3 × 10−6 m at 450 s. This study can help to establish a better relationship among different frosting stages, and better understand the plate edge effect on frosting.

Frost formation from general-low to ultra-low temperatures: A review

• Frosting mechanisms from general-low to ultra-low temperatures were investigated. • Frost morphology and properties were identified in terms of frosting factors. • Unique phenomena occurring at ultra-low temperatures were discussed. The frosting at ultra-low temperatures can cause significant degradation of the thermal performance of heat exchangers, which also leads to a decrease in the energy efficiency of air-source heat pumps. In this paper, the temperature terminologies for frosting were classified, and the frosting mechanism and frost properties were investigated from general-low to ultra-low temperatures. The dominant phase change mechanisms at general-low and ultra-low temperatures were condensation-freezing and desublimation, respectively. The frost layer growth mechanism at ultra-low temperatures can be classified into the formation of ice nuclei, growth of ice particles, and deposition of a frost layer in the initial stage of frosting. The frost morphology at ultra-low temperatures showed wisteria or shrub-shaped frost, which was not observed at general-low temperatures. Frost properties are determined depending on frosting factors such as cooling surface temperature, air temperature, absolute humidity, and air velocity, while the thermal conductivity of frost was determined by frost porosity. At ultra-low temperatures, some unusual phenomena were observed that were not observed at general-low temperatures. When the cooling surface temperature was at ultra-low temperatures, the fog was formed near the cooling surface along with the frost, and this fog was dominantly influenced by the frost surface temperature. In addition, unique phenomena such as thread-shaped frost and leading-edge frost concentrations were observed at ultra-low temperatures, and there was a clear difference in the frosting mechanism based on the temperature range.

Heat transfer in the regenerative heat exchanger

This paper tackles the issue of frost formation in non-hygroscopic rotary heat exchangers used for energy recovery from exhaust air under high-speed rotor conditions by means of numerical simulations and experimental approaches. On the basis of some idealized assumptions, a frost growth submodel is presented to predict the behavior of the rotary heat exchanger under frosting conditions. Frost formation is modeled by considering the mass diffusion of water vapor through the frost layer, taking into account supersaturation phenomena. Calculations were carried out using a three-zone model based on the modified ε-NTU method. The local heat transfer coefficient and the NTU calculation method resulting from the influence of the heat exchanger entrance region were also applied. The obtained correlations for the temperature effectiveness agree with the simulation data within uncertainty bounds. The results of the numerical simulations allowed us to determine the outdoor air conditions that initiated the frost accumulation phenomenon inside the thermal wheel for two values of return air relative humidity: RH2i=20% and RH2i=40%. In both cases, the threshold temperature for unsafe operating conditions increases with increasing relative humidity of the outdoor air. Under ‘frost accumulation’ operating conditions, the frost growth rate is approximately five times higher at RH2i=40% than at RH2i=20%. In this regard, the need to implement frost protection techniques increases significantly with an increase in relative humidity of return airflow. Further analysis conducted for the operation of a thermal wheel’s operation under frosting conditions revealed that a latent heat flux contributed to the local frost density should not be neglected in a compact heat exchanger’s model. Interestingly, the operation time of the rotary heat exchanger, and hence the growth of the thickness of the frost layer, has a significant influence on a local heat transfer coefficient α, however, it does not affect the Number of Transfer Units (NTU) visibly.

Frosting mechanism and behaviors on surfaces with simple geometries: A state-of-the-art literature review

• Correlations of frosting characteristic parameters are summarized and analysed. • Effects of frosting conditions on average frost layer characteristics are reviewed. • Frosting distribution characteristic for different cold surfaces are reviewed. • Eight research gaps relating to frosting mechanism and behaviors are identified. Frosting causes negative impacts in many technical and engineering fields, such as refrigeration, air source heat pump, aircraft, wind power generation, and power grids. To alleviate the negative impacts of frosting, studies on frosting characteristics, avoiding and delaying frosting, and defrosting mechanisms and methods have been carried out for decades. Among these studies, frosting characteristics, which are the fundamental basis for defrosting, avoiding, and delaying frosting are consistently the hot research spots. Considering that complex structures can be usually regarded as the combination of simple geometries, in this paper, a comprehensive review of the literature related to the frosting mechanism and behaviors on surfaces with simple geometries is presented. The former covers frost formation process and morphology, frost layer structure model, and frosting characteristic parameters, such as frost thickness and effective frost thermal conductivity. The latter is further divided into six parts based on the configurations of cold surfaces, including flat plates with a fixed surface temperature, flat plates with a fixed base temperature, cylinders, parallel plates, set of fins and semipermeable membranes. Based on the review, the research gaps in the related study fields are identified, and recommendations for further research are offered. The literature review presented in this paper can provide a comprehensive and systematic reference for the people who are working in the study fields where frosting is commonly encountered.

Asteroid regolith strength: Role of grain size and surface properties

Most of the small asteroids with sizes below a few km are believed to be rubble piles. In order to study the strength of such bodies, we have performed bulk measurements on simulant granular material, varying the grain size and surface properties in ambient conditions. The samples were prepared from a high-fidelity asteroid soil simulant and subjected to compression and shear stresses. We measured the material angle of repose, Young Modulus, its angle of internal friction, bulk cohesion, and tensile strength. Grain sizes were varied from 0.1 to 10 ​mm. Grain surface properties (friction and cohesive forces) were modified by adding a surface frost layer. We find that, in shear, larger grains increase the strength in confined samples, representative of regolith subsurface layers on asteroids, while they decrease strength in unconfined samples, representative of surface regolith. In compression, confined samples become weaker with increasing grain size, while unconfined samples are barely sensitive to it. We also find that increasing surface friction and intergrain cohesion increases the strength in all the samples. We measure bulk cohesion values between ∼400 and 600 ​Pa, internal friction between 25 and 45°, and tensile strengths between 600 and 900 ​Pa. The measured angles of repose varied between ∼25 and 45° in an opposite trend to the internal friction. We compare these values to spacecraft data and numerical simulations and discuss implications of our findings for rubble-pile composition and disintegration behavior. We find that grain size sorting with depth, depletion of fines at the surface, or presence of water ice in the core can provide a mechanism for regular surface shedding event on small asteroids. • We performed mechanical strength measurements on high-fidelity CI asteroid simulant. • Larger grains weaken samples in compression but strengthen it in shear. • Surface frosting on grains strengthens the samples in both compression and shear. • Measured compression and tensile strengths are in agreement with in-situ measurements at Ryugu and Bennu. • We propose potential mechanisms for regular surface shedding event on rubble-pile asteroids.

Fabrication of a superhydrophobic micron-nanoscale hierarchical structured surface for delayed icing and reduced frosting

Multifunctional superhydrophobic surfaces with dual-scale hierarchical structures have drawn considerable interest in real-world applications. The complicated fabricating process, higher costs, and poor durability limit the widespread utilization of bio-inspired superhydrophobic surfaces. Herein, we use an effective method to create a micron-nanoscale (dual-scale) hierarchical structure, which is composed of a micron-scaled rough structure constructed by a chemical-etching process and a secondary nanostructure obtained by hydrophobic nano silica (SiO2) modification. The micron-nanoscale hierarchical structured surface has superhydrophobicity with a water contact angle of 161.5°±1.9°. Compared with the micron-scaled rough structure surface, the manufactured micron-nanoscale hierarchical structured surface presented excellent anti-icing properties with a freezing delay time of 5013.6 s at -15 °C. The frost layer on the micron-nanoscale hierarchical structured surface can be rapidly melted to transform into some isolated water droplets in about 7 s due to its ultra-low water adhesion force. Additionally, the prepared superhydrophobic micron-nanoscale hierarchical structured surface has chemical stability and mechanical durability except for the delayed icing and reduced frosting performance. The construction of a micron-nanoscale hierarchical structure is expected to expand superhydrophobic surface applications in anti-icing, anti-frosting, and self-cleaning.